Tarnished coin cleaning

trout · June 19, 2015, 07:48:27 AM

This coin came back from PCGS the first time graded Genuine (99 - PVC Residue) .in a "Boddybag"
I did the acetone treatment and this is the coin now :ok:

http://www.pcgs.com/cert/32123413

5 rubles · June 19, 2015, 08:12:15 AM

Acetone does a great job removing the bulk of the contaminants, I am looking at the best solution to give that last 2% shine. There is a little bit still to be gained after the acetone bath, just have to experiment and find out how.

trout · June 19, 2015, 08:17:04 AM

Quote from: '5 rubles' pid='74592' dateline='1434667335'Acetone does a great job removing the bulk of the contaminants, I am looking at the best solution to give that last 2% shine. There is a little bit still to be gained after the acetone bath, just have to experiment and find out how.

The PVC sometimes eats the surface of the coin and no matter how many times you soak it in acetone that damage will stay there.

5 rubles · June 19, 2015, 09:31:20 AM

I can see the corrosion in some coins Caused by PVC trout, I have to admit irreversible damage has been done.
This mirror has been dipped into rinse acetone half way down. After the acetone has evaporated it leaves a cloudy surface and the bottom of the mirror where the droplet has accumulated and evaporated is more cloudier than the top. Does anyone have any ideas how to remove that?
Note that dunking the mirror in warm water does nothing to the cloud. I need something that dissolves with acetone but leaves no cloud stain behind. Or is this as good as I am going to get them?

trout · June 19, 2015, 09:40:51 AM

Looks like your acetone is contaminated Mate.

5 rubles · June 19, 2015, 10:30:45 AM

So it seems but how? it is straight out of a bottle and only few coins have gone through it so far.

You are right trout, the batch was contaminated, a new fresh rinse acetone leaves no residue, all good now. thanks for the help.
I'll be using that mirror to test my rinse batch every now and then, it shows contamination really well.

5 rubles · June 22, 2015, 09:04:06 AM

This 2002 Outback coin that has not been near the PVC sheets also present tarnishing. they are in their original RAM cardboard holders. The reverse of the coin is damaged but the obverse is fine. The plastic has the inprint of the coin visible.
Is this also PVC damage? Do the 2002 covers contain PVC?

trout · June 22, 2015, 09:43:32 AM

That outback dollar is pretty much Buggered Mate.
Heaps of people have a go at me because I remove my coins from the mint packaging and put them either in 2x2's or saflips.
THIS is why I do that :ok:

5 rubles · June 22, 2015, 09:51:46 AM

I will be pulling out all the old coins from RAM cards, they are not safe to keep coins in. It seems in the coming 20 years 99% of the RAM card coins are totally damaged so your rescued coins will be worth a lot more trout.
I think that coins kept in a jar are keeping better than in RAM plastics, that's just my opinion. I have seen others and my own old coins too, survive much better. I have had dollar coins in cardboard boxes without any cover and all they have is a nice patina.

That Outback coin is straight out of the covers and come a bit better in 24 hour acetone bath.

JeffH · June 22, 2015, 09:56:36 AM

QuoteHeaps of people have a go at me because I remove my coins from the mint packaging and put them either in 2x2's or saflips.

That is good practice in my opinion. However, try not to damage the packaging and keep it. If you ever sell the coins later then buyers do like to also get the original packaging.

5 rubles · June 22, 2015, 10:16:22 AM

When did RAM start using mylar in their packaging? Obviously they did not in the early 2000.

5 rubles · June 23, 2015, 10:36:12 AM

When using acetone bath for cleaning coins, has anyone noticed the temperature affecting the cleaning outcome? Generally warmer liquid works better than cold therefore now, during the cold months, the coins may need two day bath instead of one day bath in summer.

JeffH · June 23, 2015, 10:44:20 AM

Makes sense -Brownian Motion activity (random movement of molecules in a fluid to save you looking it up) increases with temperature.
So, put your soak container in a warm spot to minimise the time required.

Goldseeker · June 23, 2015, 03:12:43 PM

OK, now when placing coins into the Acetone, can the coins be touching or should they be kept apart?

Further, do you stand the coin on it's edge or can they be left lying down?

Yes, I know, dumb questions but I need to know please.

trout · June 23, 2015, 07:41:18 PM

Quote from: 'Goldseeker' pid='74781' dateline='1435038163'OK, now when placing coins into the Acetone, can the coins be touching or should they be kept apart?

Further, do you stand the coin on it's edge or can they be left lying down?

Yes, I know, dumb questions but I need to know please.

One coin at a time and I put a couple of tissues into the bottom of the jar so that the coin doesn't get damaged with the contact to the glass :ok: